Fair (equidistant) metal distribution and spawns

I would much prefer mirrored metal spots over mirrored maps. I hate mirrored maps, they look stupid.

The metal spots are mirrored on mirrored maps. That's one of the main points of them. Mirrored terrain as well as mirrored gameplay.

Yes I was saying I don't like mirrored terrain. I like mirrored metal spots but dislike mirrored terrain.

Now that you have the algorithm for 'distributing many points on a sphere', you can use Voronoi diagrams with the spawns as the seeds to generate an approximately uniforms tessellation on the sphere. Then, generate metal points and CSG for one tile and copy that on to the other tiles. Then you will have an algorithm for generating n-way, approximately symmetric maps.